Now Jeremy Corbyn has led Labour to a surprise comeback, it's time for the whole of his party to support him the next time

For those of us Labour supporters feeling ecstatic at the party's resilience and renaissance in the general election, there is a sad comedown with the realisation that the Tories are still in power – via an alliance with possibly the most extremist party in British politics, the Democratic Unionist Party.

Labour can but hope/expect that this true "coalition of chaos" – to quote Theresa May – is not built to last, especially in such strained circumstances of a hung parliament dealing with Brexit. Another general election looms, possibly even later this year.

And it is for that election, whenever it 'May' come, that the left must now prepare. Jeremy Corbyn and Labour were rightly ecstatic at the outcome of the election, defying awful opinion polls, driving up support, motivating the young, energising the core, and cutting the Tory lead. But next time Labour needs to actually win and that will take even more effort and planning.

Handily, Labour won't need to write a manifesto as they already have an excellent one waiting to be implemented.

So, how do Labour win the keys to Number 10?

The most important element of the next campaign must be party unity. Those who had twice fought – and lost – leadership battles against Corbyn must now become enthusiastic supporters. This is easier said than done, of course.

Labour party Leader Jeremy Corbyn gives a thumbs-up as he arrives at Labour Party headquarters the morning after the electionDaniel Leal-Olivas/AFP

No sooner had the first exit polls produced a nationwide surge in hope than one of my Labour "supporting" friends posted a Facebook comment on what might happen next: "Run on the pound, FTSE plummets. DUP and UUP would prop up the Tories. Worst news of all is my Party is locked into Corbyn for at least another 5 years. That is the true catastrophe."

Obviously, I immediately took him to task over this assessment. He was unrepentant. And, if the members of the Parliamentary Labour Party who have been noticeable by their absence in the recent campaign continue to sulk and hide, then the party may not be able to make the next step at the next opportunity.

Hilary Benn, Yvette Cooper, Heidi Alexander et al have talents and their active participation would make the Labour Party stronger. Had they been available and on-message during the election campaign perhaps not quite so much weight would have been placed upon the shoulders of Diane Abbott, who appeared to be the spokesperson on about six different departmental areas. Abbott, who has long been a target for the right-wing media, was placed under unsustainable pressure.

Already there is a new centrist motif forming that Theresa May was so poor in this election that a more moderate Labour candidate would have beaten her. But this is to ignore the fact that the Tory share of the actual vote was much in line with how it had been in opinion polls throughout the campaign. The Conservative vote did not collapse. The gap was closed by Corbyn and Labour becoming more popular. Much more popular.

This trope also ignores the fact that none of the rival candidates in the two leadership elections had been the sort of charismatic, consensual politician the centre dreams of. When a constant refrain is that the wrong Miliband Brother was chosen as leader in 2010 you know that this is the politics of straw-clutching.

It is also partly due to the disconnect between what some describe as the Westminster elite – which encompasses the media as well as the politicians. Thus, there is a failure to comprehend that Corbyn is popular because he is different. It is much like the US Democrats' inability to comprehend that Bernie Sanders was also popular because he was not seen as part of the establishment. And that he was promising real change. Hillary Clinton may have been more polished and more prepared for the presidency, but that was a large part of what made her unpopular.

Another leitmotif is Brexit for the centrists who feel most distraught about the loss of the EU Referendum and who have convinced themselves that Jeremy Corbyn could have stopped it but didn't.

Blame Cameron for Brexit. Blame Bojo. Blame Farage. Blame Gove. Blame Murdoch. Blame Dacre. But don't blame Corbyn. The Labour leader campaigned for Remain; two-thirds of Labour voters voted Remain. He offered the most honest moment of the entire campaign when he said he was 7/10 in favour of Europe. The media (and indeed most of the public) were not interested in a serious debate about Europe. Alan Johnson - occasionally touted as a great labour leader in waiting - ran Labour's EU Referendum campaign: can you remember a single thing he said or did?

How can floating voters be persuaded of a party's plan when they can point out that not even all of the party supports the plan?

The day after Brexit, Labour's centrist MPs launched a woefully miscalculated coup d'etat. When the nation needed them most, they chose to pursue their own Westminster Bubble agenda. When Labour should have been profiting from the Conservative party tearing itself apart, it was instead the left that was involved in a wasteful internecine feud.

That must not happen again. The Tory party will find itself locked into stressful and damaging squabbling after May's election gamble failed. The Conservatives will have to agree a Brexit plan while led by someone who became an electoral liability and lost her party's majority. They will be in an alliance with a political loose cannon. It's not as though the Tories have a long list of top quailty, baggage-free, popular policians lined up to take over from May either.

For Labour to continue its renaissance, Conservative problems must be the main political story. It will be one that even the Tory cheerleaders in the press will be unable to ignore. Unless Labour shoots itself in the foot again.